1. Field of the Invention
The present invention relates, in general, to a flush valve diaphragm for urinals and other plumbing equipment and, more particularly, to a flush valve diaphragm rib design and bypass orifice filter insert.
2. Description of Related Art
Typical diaphragm-type flush valves for use on toilet devices, such as urinals and water closets, utilize a flexible diaphragm to establish and to seal off the connection between an inlet and outlet of a flush valve. Typically, the diaphragm is made of an elastomeric material, such as rubber, and includes a filter and a bypass orifice which provides fluid communication between the inlet side of the flush valve and an upper chamber of the flush valve. Such flush valve diaphragms are described in U.S. Pat. No. 6,299,128 B1, which is hereby incorporated by reference in its entirety.
The performance of prior art diaphragm-type flush valves can depend upon how well the diaphragm seals off the connection between the inlet and the outlet. Inadequate sealing of the diaphragm can occur when a diaphragm loses its elasticity and becomes distorted due to the constant flexing of the diaphragm after extensive use. The performance also depends on the pressure drop between the opposite sides of the diaphragm due to the bypass orifice. A clogged bypass orifice can prevent water from flowing to the top side of the diaphragm, which results in an inadequate seal. It is desirable to provide a filtering element with the bypass orifice in order to eliminate effectively particulates, which may clog the water passageway of the bypass orifice. In addition, water hammer resulting from the diaphragm closing too quickly against the valve body can also be a problem that affects the performance of the flush valve.
It is, therefore, an object of the present invention to eliminate the above-mentioned deficiencies by providing a diaphragm assembly with improved performance, longer useful life, and service in diaphragm-type flush valves.